PERSONAL HEALTH; In Matters of the Heart, Prevention Is Key

By JANE E. BRODY

Published: July 31, 2007

If you were a cardiologist or an optimist, you might say the glass was half-full. But if you were an epidemiologist or pessimist, you would be more inclined to say the glass was half-empty.

The glass, in this case, is the death rate from coronary heart disease in the United States, which declined sharply in the last two decades of the 20th century. From 1980 through 2000, the age-adjusted death rate for coronary heart disease fell to 266.8 deaths per 100,000 men from 542.9 deaths, and to 134.4 deaths per 100,000 women from 263.3.

This change, which meant 341,745 fewer coronary deaths in 2000 than would otherwise have occurred (along with a continued decline in such deaths in the years since), catapulted cancer last year into the lead position as a killer of Americans under age 85, even though cancer death rates are also declining.

Nonetheless, the pessimists would say, far more people are still dying of heart disease than should be, often before reaching age 30, even though the tools are at hand to virtually eliminate this scourge. And there are now strong indications that as Americans continue to get fatter and fatter, the decline in heart disease deaths will soon grind to a halt and may even reverse itself.

Furthermore, the pessimists note, the direct and indirect costs of coronary heart disease are still breaking the health care bank, at $142.5 billion last year and rising.

Why the Death Rate Fell

In the June 7 issue of The New England Journal of Medicine, a team led by public health specialists from the national Centers for Disease Control and Preventionanalyzed the changes that have occurred in American medicine and habits to account for the impressive drop in deaths from coronary heart disease (the most common kind of heart disease, which results from blocked blood vessels feeding the heart).

About 47 percent of the decrease in coronary deaths among Americans aged 25 to 84, the researchers concluded, could be attributed to ''a revolution in the treatments for established coronary heart disease'': the use of medical or surgical therapies that help prevent or postpone deaths from heart disease in patients already afflicted. These are therapies administered to patients who have suffered and survived a heart attack, people with chest pains indicative of blocked coronary arteries and patients with heart failure.

The remedies range from cheap (bystander CPR to forestall death from a heart attack, for example, and daily aspirin to prevent clots that can precipitate an attack) to costly and sometimes hazardous (angioplasty, stents and coronary bypass surgery to open or circumvent blocked arteries). Other therapies include clot-dissolving drugs, drugs that lower blood pressure and cholesterol levels and rehabilitation programs to improve cardiac function.

All told, the researchers estimated, nearly 160,000 of the coronary deaths that were prevented or postponed in 2000 ''were attributable to medical therapies'' administered to patients already known to have had heart disease.

While patients and their loved ones are no doubt extremely grateful for the ability of modern medicine to keep people alive and often well when their hearts are on the verge of giving out, the therapeutic approach to curbing the coronary death rate is like shutting the barn door after the horse has escaped. A more economical, not to mention less terrifying, approach is to prevent the development of this life-threatening and costly disease.

According to the new analysis, about 44 percent of the decline in coronary mortality during the 20 years studied was due to improvements in risk factors for heart disease: reduced cholesterol levels, better control of high blood pressure, a decline in smoking and a small rise in physical activity.

These changes have occurred largely through the seriously underfinanced efforts of public health advocates who for decades have championed the cause of primary prevention of heart disease. They started in the early 1960s with campaigns against smoking, continued with efforts to curb saturated fats, cholesterol and salt in the American diet and moved on to still-lagging efforts to get more Americans to be physically active.

The pharmaceutical industry, which spends billions of dollars to develop and test new drugs and convince doctors to prescribe them for their patients, has also contributed to better control of risk factors, often in people not yet known to have heart disease. There is now a plethora of risk-reducing medications available both to healthy people and to those already afflicted, including old-school but still front-line diuretics to lower blood pressure and relatively new (and very effective) statins to lower dangerously high cholesterol levels.

There are also many aids sold over the counter and by prescription, as well as therapies like hypnosis, to help people quit smoking. In addition, a growing public intolerance for tobacco smoke, increasing limits on where people can smoke and the rising cost of cigarettes have prompted many people to quit smoking or at least cut down on how much they smoke.

What Next?

But there are two countertrends that are cause for serious concern about the future of heart disease in this country: the overall increase in weight and the accompanying increase in the prevalence of diabetes. The researchers calculated that ''increases in the body-mass index accounted over all for about 26,000 additional deaths from coronary heart disease in 2000, and increases in the prevalence of diabetes for about 33,500 additional deaths.''

So far, there is no indication of a reversal of these trends. But unless the weight issue is brought under control, two other risk factors for heart disease will also increase: serum cholesterol levels will rise, and so will blood pressure. And along with Type 2 diabetes, these increases can change the direction of coronary mortality.

No one would argue that it's better to shut the barn door while the horse is still inside. So let's talk about primary prevention.

We're doing a lot better with controlling elevated cholesterol through diet and drugs, and the recent widespread elimination of trans fats from processed foods will help even more.

We've done a lot, but could still do a lot more, to control hypertension by making sure not only that everyone with high blood pressure gets a diagnosis and treatment, but that the treatment effectively controls blood pressure and is maintained indefinitely.

Smoking, a major cause of heart attacks and sudden cardiac death, declined among adults by 50 percent from 1965 to 2005. But 45 million American adults and 20 percent of teenagers still smoke, and more effort is needed to eliminate this noxious behavior and to keep youngsters from taking it up.

Most important, perhaps, is to nip in the bud the current rise in weight and diabetes. These increases in coronary risk are environmental, not genetic, and can only be resolved by changing how and what people eat and how much they exercise.

So, my fellow Americans, I urge you to tighten your lips to culinary temptation and instead expand your lungs and blood vessels by exercising more and more often. Your heart, which will become a more efficient and effective pump, will thank you for it.